Coil box, mounted between a roughing rolling train and a finishing rolling train

ABSTRACT

The invention relates to a coil box, which is mounted between a roughing rolling train and a finishing rolling train, for metal pre-strips, in particular steel strips, which are hot wound to form coils and are protected against further cooling in the vicinity of a winding and/or unwinding station ( 6 ) by means of heat-shield devices ( 7 ) on the front faces ( 5   a;    5   b ) of the coils. The aim of the invention is to universally configure said coil box. To achieve this, the heat-shield devices ( 7 ) are configured from lateral walls ( 8; 8   b ) that can be pivoted to rest against the front faces ( 5   a;    5   b ) of the coils and a pair of opposing heat-shield devices ( 7 ) can be aligned in parallel to different coil widths ( 5   c ).

The invention concerns a coil box installed between a roughing mill anda finishing mill for metal pre-strip, especially steel pre-strip, whichis wound hot into coils and is protected from further cooling in thevicinity of a coiling and/or uncoiling station by means of heat shielddevices on the end faces of the coils.

A coil box of this type is known from EP 0,507,800 B1. Lateral walls areprovided for a mandrelless coiling process to coil the hot metallicmaterial in a first coil position. This is followed by an uncoilingstation, from which the steel strip is conveyed to the finishing mill.The heat shield lateral walls are functionally connected with themandrelless coiling or uncoiling device, which requires the samespacing. The heat shield devices are provided with a reradiating innersurface. Heat shield devices of this type are used in both the windingstation and the unwinding station. Sufficient coverage of the end facesof the coil cannot always be achieved in this way.

The objective of the invention is to develop a heat shield device ofthis type even for varying coil dimensions that are being processed inthe given rolling mill.

In accordance with the invention, this objective is achieved by formingthe heat shield devices from lateral walls that can be adjusted to theend faces of the coil by swiveling, and a pair of opposing heat shielddevices can be adjusted in parallel to different coil widths. The heatshield devices in the vicinity of the uncoiling station of a coil boxreduce the temperature difference between the edge of the strip and thecenter of the strip and also help to keep the temperature distributionin the center of the strip constant over the length of the strip. Thisproduces a better temperature distribution in the pre-strip before thepre-strip enters the finishing mill and thus results in improved qualityof the finished product. At the same time, metal strips of completelydifferent widths can be protected.

One embodiment of the invention provides that the heat shield devicescan each be adjusted to the corresponding end face of the coil bypiston-cylinder units operating in opposite directions. In this way, thespace between the edges of the strip and the lateral wall can be kept assmall as possible.

These more expensive means by no means need to impair the access to theuncoiling station. The principle of swivelability of the heat shielddevices can be utilized to swing the heat shield devices on each side ofthe coil as a unit out of the vicinity of the uncoiling station by meansof a swivel drive.

To take into account the situation in the rolling mill, it is alsoadvantageous for it to be possible, on a rear side of the coil, to swingthe heat shield device out or back in a circular path in a verticalplane about a horizontal axis of rotation by means of the swivel driveand, on a front side of the coil, to swing the heat shield device out orback in a horizontal circular path about a vertical axis of rotation bymeans of the swivel drive.

Another embodiment of the invention provides that the lateral walls aredesigned like doors that can each be swung out or closed by means of theswivel drive. This has the advantage that, in the event of a disruption,a wound coil can be removed from the coil box by means of a C-hook. Inaddition, maintenance work is facilitated by the door-like design.

In a modification of the invention, each of the heat shield devices thatcan be swung out on each side consists of a hydraulic swivel drive,bracket arms, the piston-cylinder unit, a pivoted lever, a bridge frame,and the given lateral wall, and the unit is supported on a transverseframe. Therefore, the unit can also be installed in the uncoilingstation later.

In accordance with other features, the parallel adjustment of thelateral walls is designed in such a way that outwardly projectingbracket arms, on each of which the cylinder of each piston-cylinder unitis pivoted, are mounted on the transverse frame that runs transverselyto the center of the rolling mill in the uncoiling station; that thecorresponding piston rod acts approximately in the center on a pivotedlever pivoted on the frame; and that the bridge frame, which extendsapproximately over the length of the lateral wall and on which thecorresponding lateral wall is mounted at several support points, ispivoted on the end of the pivoted lever.

On the basis of measurements that were performed, it is alsoadvantageous for the lateral wall to be covered on the hot side not onlywith insulating material but also with a foil-like layer of steel. Thesteel foil becomes hot significantly faster. Due to the direct contactof the steel foil with the insulating material, the insulating materialalso heats faster. Since the insulating effect is that much greater thehotter the inner surface temperature of the heat shield is, a heatshield with the foil achieves the full insulation faster than a heatshield without this foil.

However, the positive effect is lost if a foil that is too thick isselected. A steel sheet only 0.5 mm thick no longer has any detectableeffect. On the basis of these findings, it is advantageous for thefoil-like layer of steel to have a thickness of about 0.05-0.3 mm, andpreferably 0.1 mm.

A further improvement of the invention is realized if not only thelateral walls are provided with the insulating material, but also pairsof stabilizers adjacent to the lateral walls in the uncoiling stationare provided with the insulating material, and pairs of stabilizers inthe coiling station are also provided with the insulating material. Atthe same time, the foil-like layer of steel can be placed on theinsulating material if this makes the insulation more effective. The endfaces of the coils can be insulated even better in this way.

Embodiments of the invention are illustrated in the drawings andexplained in greater detail below.

FIG. 1 shows a side view of the section of the rolling mill thatcontains the coil box.

FIG. 2 shows a top view of the installation in direction “X” inaccordance with FIG. 1.

FIG. 3 shows a vertical section A-A in accordance with FIG. 1.

In FIG. 1, a coil box is installed between a roughing mill and afinishing mill, with a coiling station 1, in which the coil 5 is coiledby run-in rolls 2, bending rolls 3, and a shaping roll 4. The coil 5 islocated in the uncoiling station 6. In the uncoiling station 6, the coil5 is protected from further cooling at its two coil end faces 5 a, 5 b,which lie in the plane of the drawing, by means of heat shield devices 7in the vicinity of the uncoiling station 6.

Furthermore, the heat shield devices 7 are formed by lateral walls 8 a,8 b that can be adjusted to the end faces 5 a, 5 b by swiveling, and apair of opposing heat shield devices 7 can be adjusted in parallel todifferent coil widths 5 c (a maximum and a minimum coil width). Each ofthe lateral walls 8 a, 8 b is guided symmetrically to the center 9 ofthe rolling mill.

In accordance with FIG. 3, the heat shield devices 7 can each beadjusted to the corresponding end face 5 a, 5 b of the coil bypiston-cylinder units 10 operating in opposite directions.

In FIG. 2, on a front side 11 of the coil, the entire unit 15 can behorizontally swung out or swung back on a horizontal circular path 14about a vertical axis of rotation 13 a by means of a (hydraulic) swiveldrive 13, as is shown in the lower part of FIG. 2. The axis of rotationof the swivel drive 13 is perpendicular to the plane of the drawing.

Likewise, on a rear side 11 of the coil, the heat shield device 7 can beswung out or swung back again in a circular path 13 c in a verticalplane about a horizontal axis of rotation 13 b by means of the swiveldrive 13.

The lateral walls 8 a, 8 b can be designed like doors, approximately asshown in the drawing, and can be swung by means of the swivel drive 13on the vertical axis of rotation 13 a on circular path 14 to open orclose them.

In this regard, each entire unit 15 of the swiveling heat shield device7 consists of a swivel drive 13, a bracket arm 16, the piston-cylinderunit 10, a pivoted lever 17, a bridge frame 18, and the given lateralwall 8 a, 8 b, and the unit 15 is supported on a transverse frame 19(cf. FIG. 1).

In accordance with FIG. 3, outwardly projecting brackets 20 are mountedon the transverse frame 19, which runs transversely to the center 9 ofthe rolling mill. The cylinder 10 a of the piston-cylinder unit 10 ispivoted with the bracket 20. The corresponding piston rod 10 b islikewise pivoted on a pivoted lever 21, which is connected with thetransverse frame 19, and the point of application can be approximatelyin the center. A bridge frame 22, which extends approximately over thelength of the later wall 8 a, 8 b, is pivoted at the end 21 a of thepivoted lever 19, and support points 23 are formed on the bridge frame22 as connections to the lateral walls 8 a, 8 b.

The lateral walls 8 a, 8 b are covered on the hot side 24 withinsulating material 25, and the insulating material 25 is covered with afoil-like layer of steel 26. The layer of steel 26 has a thickness ofabout 0.1 mm and may be only slightly thicker or thinner.

At the same time, the following additional feature is provided (FIG. 1):Not only the lateral walls 8 a, 8 b are provided with the insulatingmaterial, but also pairs of stabilizers 27 adjacent to the lateral wallsin the uncoiling station 6 are provided with the insulating material 25,and pairs of stabilizers 28 in the coiling station 1 are also providedwith the insulating material 25. It is also advantageous for theinsulating material 25 to be covered with the foil-like layer of steel26.

List of Reference Numbers  1. coiling station  2. run-in roll  3.bending roll  4. shaping roll  5. coil  5a coil end face  5b coil endface  5c coil width  6. uncoiling station  7. heat shield device  8alateral wall  8b lateral wall  9. center of the rolling mill 10.piston-cylinder unit 11. side of the coil 12. side of the coil 13.swivel drive 13a vertical axis of rotation 13b horizontal axis ofrotation 13c circular path of the aperture angle 14. circular path 15.unit 16. bracket arm 17. pivoted lever 18. bridge frame 19. transverseframe 20. bracket 21. pivoted lever 21a end of the pivoted lever 22.bridge frame 23. support point 24. hot side 25. insulating material 26.layer of steel 27. stabilizer of the uncoiling station 28. stabilizer ofthe coiling station

1. Coil box installed between a roughing mill and a finishing mill formetal pre-strip, especially steel pre-strip, which is wound hot intocoils and is protected from further cooling in the vicinity of a coilingand/or uncoiling station by means of heat shield devices on the endfaces of the coil, wherein the heat shield devices (7) are formed bylateral walls (8 a; 8 b) that can be adjusted to the end faces (5 a; 5b) of the coil by swiveling, and a pair of opposing heat shield devices(7) can be adjusted in parallel to different coil widths (5 c), whereinthe heat shield devices (7) on each side of the coil (11; 12) can beswung as a unit (15) out of the vicinity of the uncoiling station (6) bymeans of a swivel drive (13).
 2. Coil box in accordance with claim 1,wherein the heat shield devices (7) can each be adjusted to thecorresponding end face (5 a; 5 b) of the coil by piston-cylinder units(10) operating in opposite directions.
 3. Coil box in accordance withclaim 1, wherein, on a rear side (11) of the coil, the heat shielddevice (7) can be swung out or back in a circular path (13 c) in avertical plane about a horizontal axis of rotation (13 b) by means ofthe swivel drive (13) and, on a front side (12) of the coil, the heatshield device (7) can be swung out or back in a horizontal circular path(14) about a vertical axis of rotation (13 a) by means of the swiveldrive (13).
 4. Coil box in accordance with claim 1, wherein the lateralwalls (8 a; 8 b) are designed like doors that can each be swung out orclosed by means of the swivel drive (13).
 5. Coil box in accordance withclaim 1, wherein each of the heat shield devices (7) that can be swungout on each side (11; 12) consists of a hydraulic swivel drive (13),bracket arms (16), a piston-cylinder unit (10), a pivoted lever (17), abridge frame (18), and the given lateral wall (8 a; 8 b), and the unit(15) is supported on a transverse frame (19).
 6. Coil box in accordancewith claim 5, wherein outwardly projecting brackets (20), on each ofwhich the cylinder (10 a) of each piston-cylinder unit (10) is pivoted,are mounted on a transverse frame (19) that runs transversely to thecenter (9) of the rolling mill in the uncoiling station (6); that thecorresponding piston rod (10 b) acts approximately in the center on apivoted lever (21) pivoted on the transverse frame (19); and that abridge frame (22), which extends approximately over the length of thelateral wall (8 a; 8 b) and on which the corresponding lateral wall (8a; 8 b) is mounted at several support points (23), is pivoted on the end(21 a) of the pivoted lever (21).
 7. Coil box in accordance with claim1, wherein the hot side (24) of the lateral wall (8 a; 8 b) is coverednot only with insulating material (25) but also with a layer of steelfoil (26).
 8. Coil box in accordance with claim 7, wherein the foil-likelayer of steel (26) has a thickness of about 0.05-0.3 mm.
 9. Coil box inaccordance with claim 7, wherein not only the lateral walls (8 a; 8 b)are provided with the insulating material (25), but also pairs ofstabilizers (27) adjacent to the lateral walls in the uncoiling station(6) are provided with the insulating material (25), and pairs ofstabilizers (28) in the coiling station (1) are also provided with theinsulating material (25).